<!DOCTYPE html>
<html lang="ja">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>フラッシュ暗算/Flash mental arithmetic</title>
<link rel="stylesheet" href="flash.css">
</head>
<body>
<h1>フラッシュ暗算/Flash mental arithmetic</h1>
<div id="flash-container">
<div id="focus-text" class="white-text" style="display: none;">集中!/Focus!</div>
<div id="number-display">0</div>
<label for="num-select">表示する数字の数/Number of numbers to display:</label>
<select id="num-select">
<option value="3">3(難易度:簡単/Difficulty:Easy)</option>
<option value="5">5(難易度:普通/Difficulty:Normal)</option>
<option value="10">10(難易度:難しい/Difficulty:Hard)</option>
</select><br/>
<button id="start-button">Start</button>
<input type="text" id="answer" placeholder="答えを入力/Enter answer">
<button id="check-button">Check</button>
</div>
<div id="result"></div>
<script src="flash.js"></script>
</body>
</html>
